Ubuntu installer sees empty partition table

[EpsilonDelta]

I recently reinstalled win xp, so I needed to restore the boot menu with the live cd to be able to dualboot again. I followed to how-to, and it failed.
So I decided to also reinstall ubuntu with the live cd. However, the installer sees only an empty partition table, and the only option I have is to create a new partition table. gparted shows my hd as unallocated space.
Did reinstalling windows mess up my partitions?
I can still access all partitions through the live cd, so I made a backup of my linux files. But is there any way to reinstall ubuntu without formatting the entire hd?
Here's the output from sudo fdisk -lu

omitting empty partition (5)

Disk /dev/sda: 320.0 GB, 320072933376 bytes
255 heads, 63 sectors/track, 38913 cylinders, total 625142448 sectors
Units = sectors of 1 * 512 = 512 bytes
Disk identifier: 0x006d006d

Device Boot Start End Blocks Id System
/dev/sda1 * 63 263465999 131732968+ 7 HPFS/NTFS
/dev/sda2 263466000 625121279 180827640 f W95 Ext'd (LBA)
/dev/sda3 314568828 625121279 155276226 7 HPFS/NTFS
/dev/sda5 263466126 312367859 24450867 83 Linux
/dev/sda6 312367923 314568764 1100421 82 Linux swap / Solaris

[taurus]

When you get to the partition screen, pick the Manual option and mount /dev/sda5 to / (root filesystem) and format it. You don't have to do anything with /dev/sda6 (swap partition) since the installer knows how to handle it.

Remember, you need to give a mount point for /dev/sda5, /, or the installer will complain about no root filesystem defined.

[caljohnsmith]

Here's the output from sudo fdisk -lu


omitting empty partition (5)

Disk /dev/sda: 320.0 GB, 320072933376 bytes
255 heads, 63 sectors/track, 38913 cylinders, total 625142448 sectors
Units = sectors of 1 * 512 = 512 bytes
Disk identifier: 0x006d006d

Device Boot Start End Blocks Id System
/dev/sda1 * 63 263465999 131732968+ 7 HPFS/NTFS
/dev/sda2 263466000 625121279 180827640 f W95 Ext'd (LBA)
/dev/sda3 314568828 625121279 155276226 7 HPFS/NTFS
/dev/sda5 263466126 312367859 24450867 83 Linux
/dev/sda6 312367923 314568764 1100421 82 Linux swap / Solaris
Any time fdisk reports "omitting empty partition (X)", unfortunately that is a sure sign that your partition table is corrupt; that would explain why the installer can not recognize your partitions. As shown highlighted above in red, your sda3 primary partition is inside of your sda2 extended partition; thus sda3 should either be a logical partition, or your sda2 extended partition should be resized so it does not contain sda3. Unfortunately having your partition table corrupted sometimes happens when you reinstall Windows, because the Windows partitioner can use slightly different rules than the standard most Linux partition programs use; thus Windows can't adequately deal with a drive that's been partitioned with linux tools, and Windows ends up corrupting the partition table. If you would like help fixing your partition table, how about posting:

sudo sfdisk -d /dev/sda
sudo mount /dev/sda3 /mnt && ls -l /mnt
And also, do you have any preference whether sda3 is a logical or primary partition? If it does not have Windows installed to it, I would recommend making it a logical partition, because that usually gives you maximum flexibility when repartitioning.

[EpsilonDelta]

sudo sfdisk -d /dev/sda

# partition table of /dev/sda
unit: sectors

/dev/sda1 : start= 63, size=263465937, Id= 7, bootable
/dev/sda2 : start=263466000, size=361655280, Id= f
/dev/sda3 : start=314568828, size=310552452, Id= 7
/dev/sda4 : start= 0, size= 0, Id= 0
/dev/sda5 : start=263466126, size= 48901734, Id=83
/dev/sda6 : start=312367923, size= 2200842, Id=82


sudo mount /dev/sda3 /mnt && ls -l /mnt

total 96
drwxrwxrwx 1 root root 28672 2009-01-29 13:55 a3a1a4ba37747b3f21be619a
drwxrwxrwx 1 root root 4096 2009-01-08 13:13 art
drwxrwxrwx 1 root root 0 2009-02-02 17:50 fraps
drwxrwxrwx 1 root root 8192 2009-02-15 19:47 games
drwxrwxrwx 1 root root 8192 2009-01-29 18:47 install
drwxrwxrwx 1 root root 20480 2009-02-16 11:40 music
drwxrwxrwx 1 root root 4096 2009-02-09 19:37 programming
drwxrwxrwx 1 root root 0 2009-01-29 13:54 RECYCLER
drwxrwxrwx 1 root root 4096 2008-12-23 11:17 shared_doeke
drwxrwxrwx 1 root root 4096 2008-03-17 20:30 System Volume Information
drwxrwxrwx 1 root root 12288 2009-02-20 19:32 torrents
drwxrwxrwx 1 root root 0 2009-02-08 13:29 ubuntu_backup
drwxrwxrwx 1 root root 4096 2008-08-01 13:23 websites


And also, do you have any preference whether sda3 is a logical or primary partition?
No I don't, as you can see it's just data, windows is on sda1.
Is there any way I can save at least my windows partitions?

[caljohnsmith]

No I don't, as you can see it's just data, windows is on sda1.
Is there any way I can save at least my windows partitions?
The partition table problem that the Windows installer caused is simple and not serious; fortunately it should not be a big deal for us to fix your partition table so you won't lose any of your partitions. How about downloading the attached "partition_table.txt" file to your Ubuntu Live CD desktop, and then do:

sudo sfdisk --no-reread -f /dev/sda < ~/Desktop/partition_table.txt
And please post the output. Then reboot your Live CD (it is important to reboot), and please post the output of:

sudo fdisk -lu
sudo parted /dev/sda print
sudo grub
grub> root (hd0,4)
grub> setup (hd0)
grub> quit
And we can work from there.

[EpsilonDelta]

Thanks for helping me. I can now access my linux partitions from windows, and the boot menu is back. But booting from my ubuntu partition fails: "error 17, could not mount selected partition".
Here are all the outputs:


ubuntu@ubuntu:~$ sudo sfdisk --no-reread -f /dev/sda < ~/Desktop/partition_table.txt

Disk /dev/sda: 38913 cylinders, 255 heads, 63 sectors/track
Old situation:
Units = cylinders of 8225280 bytes, blocks of 1024 bytes, counting from 0

Device Boot Start End #cyls #blocks Id System
/dev/sda1 * 0+ 16399 16400- 131732968+ 7 HPFS/NTFS
/dev/sda2 16400 38911 22512 180827640 f W95 Ext'd (LBA)
/dev/sda3 19581+ 38911 19331- 155276226 7 HPFS/NTFS
/dev/sda4 0 - 0 0 0 Empty
/dev/sda5 16400+ 19443 3044- 24450867 83 Linux
/dev/sda6 19444+ 19580 137- 1100421 82 Linux swap / Solaris
New situation:
Units = sectors of 512 bytes, counting from 0

Device Boot Start End #sectors Id System
/dev/sda1 * 63 263465999 263465937 7 HPFS/NTFS
/dev/sda2 263466000 625121279 361655280 5 Extended
/dev/sda3 0 - 0 0 Empty
/dev/sda4 0 - 0 0 Empty
/dev/sda5 263466126 312367859 48901734 83 Linux
/dev/sda6 312367923 314568764 2200842 82 Linux swap / Solaris
/dev/sda7 314568828 625121279 310552452 7 HPFS/NTFS
Successfully wrote the new partition table

Re-reading the partition table ...
BLKRRPART: Device or resource busy

If you created or changed a DOS partition, /dev/foo7, say, then use dd(1)
to zero the first 512 bytes: dd if=/dev/zero of=/dev/foo7 bs=512 count=1
(See fdisk(8).)

Reboot

ubuntu@ubuntu:~$ sudo fdisk -lu

Disk /dev/sda: 320.0 GB, 320072933376 bytes
255 heads, 63 sectors/track, 38913 cylinders, total 625142448 sectors
Units = sectors of 1 * 512 = 512 bytes
Disk identifier: 0x006d006d

Device Boot Start End Blocks Id System
/dev/sda1 * 63 263465999 131732968+ 7 HPFS/NTFS
/dev/sda2 263466000 625121279 180827640 5 Extended
/dev/sda5 263466126 312367859 24450867 83 Linux
/dev/sda6 312367923 314568764 1100421 82 Linux swap / Solaris
/dev/sda7 314568828 625121279 155276226 7 HPFS/NTFS
ubuntu@ubuntu:~$ sudo parted /dev/sda print
Model: ATA SAMSUNG HD321KJ (scsi)
Disk /dev/sda: 320GB
Sector size (logical/physical): 512B/512B
Partition Table: msdos

Number Start End Size Type File system Flags
1 32.3kB 135GB 135GB primary ntfs boot
2 135GB 320GB 185GB extended
5 135GB 160GB 25.0GB logical ext3
6 160GB 161GB 1127MB logical linux-swap
7 161GB 320GB 159GB logical ntfs


grub> setup (hd0)
Checking if "/boot/grub/stage1" exists... yes
Checking if "/boot/grub/stage2" exists... yes
Checking if "/boot/grub/e2fs_stage1_5" exists... yes
Running "embed /boot/grub/e2fs_stage1_5 (hd0)"... 16 sectors are embedded.
succeeded
Running "install /boot/grub/stage1 (hd0) (hd0)1+16 p (hd0,4)/boot/grub/stage2
/boot/grub/menu.lst"... succeeded
Done.

[caljohnsmith]

It looks like your partition table is OK now, so hopefully you won't have to reinstall Windows again in the near future. How about doing the following:

sudo mount /dev/sda5 /mnt && gksudo gedit /mnt/boot/grub/menu.lst
Although I haven't seen your menu.lst, probably all the Ubuntu entries are using the wrong (hdX,Y) references; they should all be (hd0,4). If they do need to be changed to (hd0,4), be sure to also change the "#groot..." line:

# groot=(hd0,4)
If you run into any problems, please post your entire menu.lst. Otherwise let me know if that works to boot Ubuntu or not.

[EpsilonDelta]

Thanks! I changed all root(hd0,5) to (hd0,4), and my ubuntu boots again. Again, thanks for all the help!

[caljohnsmith]

You're certainly welcome, and I'm really glad to hear you can boot both Ubuntu and Windows again; cheers and have fun with your dual-boot Windows/Ubuntu setup. :)

[nghalion]

Hello Everyone,

I have THE SAME EXACT PROBLEM. I installed WinXP (one of my biggest mistakes) after Ubuntu and this lead to the corrupted partition table. The only difference is that I want to restore the Primary partition having 'Windows'. What should my partition file look like?

Here's the outputs that I get for the following:

sudo sfdisk -d /dev/sda
# partition table of /dev/sda
unit: sectors

/dev/sda1 : start= 63, size= 690732, Id= b, bootable
/dev/sda2 : start= 690795, size= 48146805, Id=83
/dev/sda3 : start= 48837600, size=263739105, Id= 5
/dev/sda4 : start=303532173, size= 9044532, Id=82
/dev/sda5 : start= 48837726, size=205085664, Id=83
/dev/sda6 : start=253923453, size= 29302497, Id=83
/dev/sda7 : start=283226013, size= 20306097, Id= 7
sudo mount /dev/sda7 /mnt && ls -l /mnt
total 2095148
drwxrwxrwx 1 root root 4096 2009-09-22 14:35 Documents and Settings
-rwxrwxrwx 1 root root 2145386496 2009-09-22 15:24 pagefile.sys
drwxrwxrwx 1 root root 8192 2009-09-22 14:58 Program Files
drwxrwxrwx 1 root root 0 2009-09-22 14:46 RECYCLER
drwxrwxrwx 1 root root 4096 2009-09-22 14:35 System Volume Information
drwxrwxrwx 1 root root 0 2009-09-22 14:58 Temp
drwxrwxrwx 1 root root 28672 2009-09-22 15:31 WINDOWSI would've tried creating my own partition table but I'm afraid I'll mess things up. Any help is greatly appreciated.

Thanks in advance.

[nghalion]

And Oh..the output for:


sudo fdisk -l

omitting empty partition (5)

Disk /dev/sda: 160.0 GB, 160041885696 bytes
255 heads, 63 sectors/track, 19457 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Disk identifier: 0x0000bb3d

Device Boot Start End Blocks Id System
/dev/sda1 * 1 43 345366 b W95 FAT32
/dev/sda2 44 3040 24073402+ 83 Linux
/dev/sda3 3041 19457 131869552+ 5 Extended
/dev/sda4 18895 19457 4522266 82 Linux swap / Solaris
/dev/sda5 3041 15806 102542832 83 Linux
/dev/sda6 15807 17630 14651248+ 83 Linux
/dev/sda7 17631 18894 10153048+ 7 HPFS/NTFS

Thanks again.